Update more core classes to use OVERRIDE / FINAL when needed

Source/core/fetch/StyleSheetResourceClient.h

Index: Source/core/fetch/StyleSheetResourceClient.h
diff --git a/Source/core/fetch/StyleSheetResourceClient.h b/Source/core/fetch/StyleSheetResourceClient.h
index 8597200568aa3955557b0d21f77bae85861cb436..05a6a4876707e2f5369f8df3c4fbb4200d5fae94 100644
--- a/Source/core/fetch/StyleSheetResourceClient.h
+++ b/Source/core/fetch/StyleSheetResourceClient.h
@@ -37,7 +37,7 @@ class StyleSheetResourceClient : public ResourceClient {
 public:
     virtual ~StyleSheetResourceClient() { }
     static ResourceClientType expectedType() { return StyleSheetType; }
-    virtual ResourceClientType resourceClientType() const { return expectedType(); }
+    virtual ResourceClientType resourceClientType() const OVERRIDE FINAL { return expectedType(); }
     virtual void setCSSStyleSheet(const String& /* href */, const KURL& /* baseURL */, const String& /* charset */, const CSSStyleSheetResource*) { }
     virtual void setXSLStyleSheet(const String& /* href */, const KURL& /* baseURL */, const String& /* sheet */) { }
 };